This invention relates generally to agricultural combines, and more particularly, to a multi-tier or surface crop residue flow guide for the discharge outlet of a vertical crop residue spreader and/or chopper, the tiers or surfaces of which direct or guide portions of a discharged flow of crop residue along vertically different outwardly directed flow paths so as to be better and more evenly distributed over a larger region of an agricultural field from which the crop was harvested.
Currently, combines typically include a straw chopper and/or straw spreader for disposing of straw and other residue separated from the harvested crop onto the crop field. In addition, some combines have a chaff spreader for spreading chaff residue separated from the grain by the cleaning apparatus or system onto the crop field. In many instances it is desirable for the straw, chaff and other residue to be spread as evenly as possible over the width or swath of that section of the field over which the combine has just passed and harvested crop from, to avoid problems resulting from uneven spreading, such as, but not limited to, difficulty in passage of fall tillage tools through residue clumps or thick areas; uneven insulation of the field resulting in uneven field warming and thawing and crop emergence during the following planting season; and increased rodent and insect habitat. In some instances, it is also desirable to have an ability to adjust the spreading to compensate for crop type, moisture and weather conditions, and the like, and also combine header width.
Although various crop residue spreaders are known which can propel residue a distance equal to about one half the width of a typical combine header, many suffer from shortcomings, including a tendency to propel heavier items of residue farther away while lighter items travel only a shorter distance. It is also known to provide deflectors and flow guides for crop residue spreaders having multiple flow channels, but the known flow channels are generally horizontally coplanar and arranged in sequential order along in the direction of rotation of the rotor or impeller of the spreader and/or chopper, which is also at least generally horizontal, and has been found to distribute and spread the residue more widely, but not as evenly as desired.
Thus, what is sought is a crop residue flow guide for the discharge outlet of a vertical rotary crop residue spreader and/or chopper, that is, one including an impeller or rotor rotatable about a generally horizontal rotational axis, having a capability to direct or guide portions of a discharged flow of crop residue outwardly along vertically different flow paths so as to be better and more evenly distributed over a larger region of an agricultural field from which the crop was harvested, to avoid shortcomings and problems of the prior art devices discussed above.
What is disclosed is a multi-tier or surface crop residue flow guide for a rotary crop residue spreader of an agricultural combine which overcomes many of the problems discussed above. The rotary spreader includes an element disposed in a housing and rotatable in a predetermined direction about an axis oriented horizontally or at a small acute angle to horizontal for driving a flow of crop residue through a discharge opening of the housing located at a predetermined angular position around the axis. The flow guide of the invention includes at least two vertically spaced guide surfaces or tiers having inlet ends disposed in at least generally axially side by side relation adjacent to the discharge opening in position for directing portions of the flow of crop residue in generally the predetermined direction radially away from the opening, respectively, each of the flow guides having a curved surface connected to the inlet end thereof and extending generally in the predetermined direction radially outwardly away from the discharge opening to a discharge end spaced radially outwardly from the spreader for directing the respective portion of the flow of the crop residue radially outwardly away from the spreader, the curved surfaces and discharge ends of the flow guides being radially or vertically offset or separated one relative to the other such that the portions of the flow of the crop residue will follow vertically different flow paths or trajectories away from the spreader.
According to a preferred aspect of the invention the flow guides can be mounted or connected to the spreader for pivotal or other movement upwardly and downwardly and possibly fore to aft to allow moving the flow guides through a range of positions for achieving a desired residue trajectory and distribution over a crop field. One or more deflector panels can also be disposed along the flow paths for further directing and controlling or damping the flow of crop residue.